Mixtures comprising polyacrylonitrile and polymeric ester-lactones



Patented Nov. 13, 1951 UNITED v STATES I PATENT osslcs MIXTURES COMPRISING POLYAGRYLONI- TBILE AND POLYMERIC ESTEB-LACTONES Barry W. Coover, Jr., 'Kinrsliort, Tenn, and

Joseph B. Dickey, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. 2., a

corporation of New Jersey No Drawing. Application April 29, 1959,

Serial No. 159,144

, l 18 Claims. (Cl. 260-30.!) 2

This invention relates to polymer compositions provide polymer mixtures comprising polyac- .comprising polyacrylonitrlle and polymeric esterrylonitrile and polymeric ester-lactones. lactones, and to articles prepared therefrom. Another object of our invention is to provide Acrylonitriie has previously been used in the methods for making these mixtures. preparation of various polymers which are char- 5 A further object of our inventionis to provide acterized by insolubility, or very low solubility, homogeneous solutions of these polymer mixtures. in many of the usual organic solvents. Many of Other objects will become apparent from a conthese polymers, especially those containing high sideration of the following description and expercentages of acrylonitrile, are further charamples. Y J acterized by their lack of susceptibility to organic According to our invention. we provide polymer dyes, it being well known that fibers spun from mixtures comprising from 60 to 90 per cent by polyacrylonitrlle solutions can be passed through weight of polyacrylonitrile (i. e. a homopolymer dye baths without material amounts of the dye of acrylonitrile) and from 40 to 10 per cent by adhering to the fiber. V W h f a p ym ri e ter-lactone of maleic an- Attempts have been made to increase the dyehydride and an ester selected from the group ability of polyacrylonitrlle fibers by interpolyconsisting of'vinyl acetate and'isopropenylacemerizing acrylonitrile with certain monomers tate. Quite unexpectedly, we have found that whose polymers have an afilnity for dyes. While polymeric compositions having the above range this procedure does give polymer. products from of components are excellently adaptable for the which fibers having good dyeing properties can go spinning of fibers in that they have a highsoftbe obtained, a serious drawback arises in cerening point, and provide fibrous products showtain instances due to a substantial lowering of mg no perceptible segmentation. the softening point of the fiber. For example, The polymeric ester-lactones of maleic anhywhile an interpolymer of acrylonitrile and acrylic dride and isopropenyl acetate which we employ acid containing about 80 per cent by weight of in our invention have previously been described acrylonitrile and 20 per cent by weight of acrylic in U. S. Patent 2,481,769, dated September acid in the polymer molecule, can be drawn into 13, 1949. The process described in that patent fibers readily susceptible to dyes, the softening comprises heating to reacting temperature an point of such fibers is too low for practical purequimolar heteropolymer of isopropenyl acetate poses, softening of the fibers being observed at no and maleic anhydride anda saturated monohyabout 150-170 C. dric alcohol containing from 1 to 12 carbon Other attempts have been made to increase atoms, in the presence of an acid-esterification the dyeability of polyacrylonitrlle fibers by mixcatalyst. ing with the polyacrylonitrlle, before spinning, Temperatures used for the esterification (i. e. other polymeric materials which are dye-susinner esterification, or lactonization) vary fromceptible. This procedure likewise provides fibers about 30 C. to the reflux temperature of the rehaving good dyeing properties, however, many of action mixture, although the temperature can these fibers show a low softening point, and in be varied according to the requirements of the addition many show segmentation into their in-' operator. If desired, an inert organic solvent, dividual components along their horizontal axis. 40 or diluent, e. g. 1,4-dioxane, benzene. carbon For example, fibers spun from solutions of mixtetrachloride, acetone, ethylene dichloride. n-

tures of polyacrylonitrlle and polyvinyl acetate, hexane, toluene, etc. can be used. A solvent is are too low in softening temperature to be of especially useful where a high molecular weight practical value, and also are subject to the defect alcohol is used in the esterificatim e. g. lauryl of segmentation. This is not surprising because alcohol (dodecyl alcohol).

it is generally known that polyacrylonitrlle is The acid-esterification catalysts, used in prenot compatible with many organic (or inorganic) paring the polymeric ester-lactones of our insubstances. vention, have previously been used in the art of We have now found new resinous compositions esterification of acids, or anhydrides, and algowhich provide fibers having higher softening 5o hols. Typical catalysts include sulfuric acid. points than the interpolymers referred to above. Ph pho ic c hydrochloric acid, hydr fl oric and which do not exhibit the segmentation deci methanesulfcnlc id, ethanesulfonic acid, feet shown by many of the fibers prepared from n-butanesulfonic acid, benzenesulfonic acid, 0-, certain prior art polymer mixtures comprising m-, and p-toluenesulfonic acids, ethanedisulfonic polvacrylonitrile. acid, etc. t

It is, therefore, an object of our invention to The alcohols useful in the esterification' in- I 3 clude the saturated aliphatic, monohydric alcohols containing from 1 to 12 carbon atoms. Those alcohols containing from 5 to 12 carbon atoms are especially useful. Other details of the procedure for esterifying the heteropolymer 'of isopropenyl acetate and maleic anhydride can be found in U. S. Patent 2,481,769.

The polymeric ester-lactones of maleic anhydride and vinyl acetate which we employ in our invention have previously been described in U. S. Patent 2,306,071, dated December 22, 1942. In general, these ester-lactones can beprepared according to the directions set out above. although the reaction proceeds more readily than that wherein the ester-lactones of isopropenyl acetate and maleic anhydride are prepared. While the ester-lactones prepared from the isopropenyl acetate heteropolymer differ somewhat from those prepared from the vinyl acetate heteropolymer, we have found that both types of ester-lactones are suitable for the purposes of our invention.

The polyacrylonitrile and polymeric ester-lac tone resins can be mixed together by any of several methods. The two ingredients can be mixed together in a suitable mixer, such as a ball mill, or they can be dissolved in a mutual solvent (which is known to dissolve polyacrylonitrile), such as N,N-dimethylformamide, N,N-

which is agitated and heated to effect solution.,

Thesolubility of the resins in the solvents can be improved by incorporating a small amount of certain acids, such as sulfuric acid, phosphoric acid, oxalic acid, etc. as has been described in the .copending applications Serial No. 49,654 and Serial No. 49,655, both filed September 16, 1948, of H. W. Coover, Jr., T. E. Stanin, and Joseph B. -Dickey, now Patents Nos. 2,503,244 and 2,503,245, issued April 11, 1950. The concentration of solids in the solvents can be varied, depending on the use to which the composition is to. be put; however, for most purposes it has been found that from about to 40 per cent by weight of solids is adequate.

Other solvents which can be usedin the preparation of solutions from our new compositions include N,N-dimethylmethoxyacetamide, d1- methylcyanamide, N,N-dimethylcyanoacetamide, N,N dimethyl-p-cyanopropionamide, glycolonitrile (formaldehyde eyanohydrin) malononitrile, ethylenecyanohydrin, dimethylsulfoxide, dimethyl sulfone, tetramethylene sulfone, tetramethylene sulfoxide, N-formylpyrrolidine, N-formylmorpholine, N,N'-tetramethylmethanephosphonamide, etc. Generally speaking. these solvents are not as advantageous as the solvents referred to above.

-.'I-he following examples illustrate methods for utilizing the new compositions of our invention.

Example 1 g; of'a mixture containing 20 per cent by weight of the n-amyl ester-lactone of an equimolar-heteropolymer of isopropenyl acetate and maleic anhydride (prepared as described in Example VI of U. 8. Patent 2,481,769) and 80 per cent by weight of polyacrylonitrile were dissolved in 80 g. of N,N-dimethylformamide, and the .4 solution was filtered under pressure into a stainless steel chamber, which had a single-hole spinneret measuring 0.1 mm. in diameter. ex

tending horizontally from the bottom of the chamber in such a manner that upon extrusion,

a right angley to the chamber, and contained water. The filament coagulated upon coming into contact with the water, and was then taken up on a roller having a peripheral speed of 16 feet per minute. The filament passed from this roller through a hot air chamber heated at 170-200 C. and onto a wind-up drum .one meter in circumference, which was rotating at a surface speed of 59.2 feet per minute. After the drum had made 50 revolutions an automatically controlled guide was shifted one inch to an adjacent position on the drum and the drum was allowed to make another 50 revolutions. This was continued until several such 50-filament bundles werev obtained. These were cut from the drum and the bundles containing 50 filaments, each measuring one meter in length, were separately twisted to obtain several one meter lengths of yarn. The samples thus produced had a tenacity of 3.6 grams per denier, an extensibility of 15 per cent at break, and shrank 8 per cent in boiling water.

Example 2 In a manner similar to that described in Ex.- ample 1 above, a N,N-dimethylformamide solution of a mixture containing 20 per cent by weight of an ethyl ester-lactone of an equimolar isopropenyl acetate-maleic anhydride meteropolymer (prepared as described in Example 11 of U. S. Patent 2,481,769) and 80 per cent by weight of acrylonitrile was spun into fibers one meterin length. They had a tenacity of 3.1 grams per denier, an extensibility of 14 per cent at break, and shrank only 9 per cent in boiling water.

Example 3 In a manner similar to that described in Example 1 above, a N,N-dimethylformamide solution of a mixture containing 20 per cent by weight of n-butyl ester-lactone of an equimolar heteropolymer of vinyl acetate and maleic anhydride (prepared as described in Example 4 of U. S. Patent 2,306,071) and 80 per cent by weight of polyacrylonitrile was spun into fibers one meter in length. They had a tenacity of 4.1 grams per denier, an extensibility of 11 per cent at break, and shrank 8 per cent in boiling water.

Example 4 In a manner similar to that described in Example 1 above, a N,N-dimethylformamide solution of a mixture containing 10 per cent by weight of the isoamyl ester-lactone of an equimolar heteropolymer of isopropenyl .acetate and maleic anhydride (prepared as described in Example VII of U. S. Patent 2,481,769) and per cent by weight of polyacrylonitrile was spun into fibers one meter in length. The fibers had a tenacity of 4.2 grams per denier, an extensibility of 18 per cent at break, and shrank only 7 per cent in boiling water.

Example 5 'VIII of U. S. Patent 2,481,769) and 60 per cent by weight of polyacrylonitrile was spun into fibers one meter in length. They had a tenacity of 2.8 grams per denier, an extensibility of 16-per cent at break, and shrank 13 per cent in boiling water.

Example 6 In a manner similar to that described in Example 1 above, a N,N-dimethylformamide solution of a mixture containing 30 per cent by weight of the methyl ester-lactone of an equimolar heteropolymer of isopropenyl acetate and maleic anhydride (prepared as described in U. S. Patent 2,481,769) and 70 per cent by weight of polyacrylonitrile was spun into fibers one meter in length. They had a tenacity of 3.1 grams per denier, an extensibility of 17 per cent at break, and shrank per cent in boiling water.

Example 7 In a manner similar to that described in Ex-- ample 1 above, a N,N-dimethylformamide-solution of a mixture containing 25 per cent by weight of the ethyl ester-lactone of. an equimolar heteropolymer of isopropenyl acetate and maleic anhydride (prepared as described in Example H 01' U. S. Patent 2,481,769) and 75 per cent by weight of polyacrylonitrile was spun into fibers one meter in length. They had a tenacity of 3.4 grams per denier, an extensibility of 14 percent at break, and. shrank only 9 per cent in boiling water.

Solvents other than N,N-dimethylformamide can advantageously be used in the preparation of synthetic fibers and yarns of our invention, including thoses solvents which have been listed above. The fibers can be spun into a drying atmosphere or they can be spun into a precipitating bath containing a liquid in which polyacrylonitrile is insoluble, e. g. water.

The polyacrylonitrile useful in practicing our invention can be prepared according to the process described in U. S. Patent 2,434,054, dated January 6, 1948, or U. S. Patent 2,296,403, dated September 22, 1942. Other processes which can be used are described in the copending applications, Serial No. 49,651, Serial No. 49.652, and Serial No. 49,653, all filed September 16, 1948, of

T. E. Stanin, H. M. Coover, Jr., and J. B. Dickey.

The amount of ester-lactone resin used in preparing the polymer compositions of our invention has a marked effect on the physical and chemical properties of the resulting fibers which are prepared from these mixtures. For example, fibers spun from mixtures containing less than about 10 per cent of the ester-lactone resin cannot be satisfactorily dyed, whereas fibers spun from polymeric mixtures containing more than about 40 per cent by weight of the ester-lactone resin do. not exhibit the high softening points which characterize the fibers prepared according to the above examples.

The compositions of our invention can also be used in the preparation of sheets, films, tapes, etc.

What we claim as our invention and desire secured by Letters Patent 0! the United States is: 1., A resinous composition comprising from 80 to per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight of an esterlactone prepared by heating to reacting temperatureone molecular proportion of an equimolar heteropolymer of maleic anhydride and an ester selected from the group consisting of vinyl acetate and isopropenyl acetate, with from 2 to 25 -molecular proportions of a saturated monohydric aliphatic alcohol containing from 1 to 12 carbon atoms in the presence of an acid-esteriflcation catalyst.

2. A resinous composition comprising from 60 to 90 per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight of an esterlactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer of maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of a saturated monohydric aliphatic alcohol containing from 1 to 12 carbon atoms in the presence of an acid-esterification catalyst.

3. A resinous composition comprising from 60 to 90 per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight of an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer of maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of a saturated monohydric aliphatic alcohol containing from 5 to 12 carbon atoms in the presence of sulfuric acid.

4. A resinous composition comprising from 60 to 90, per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight of an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer of. maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of ethyl alcohol in the presence of an acid-esterification catalyst.

5. A resinous composition comprising from 60 to 90 per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight of an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer of maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of isopropyl alcohol in the presence of an acid-esterification catalyst.

6. A resinous composition comprising from 60 to 90 per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight of an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer of maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of n-amyl alcohol in the presence of an acid-esterification catalyst.

'7. A resinous composition comprising from 60 to 90 per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight of an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer of maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of isoamyl alcohol in the presence of an acld-esteriflcation catalyst.

8. A solution of a resinous composition comprising i'rom 60 to 90 per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight 7 acting temperature one molecular proportion of an equimolar heteropolymer oi maleic anhydride and an ester selected from the group consisting of vinyl acetate and isopropenyi acetate, with from 2 to 25 molecular proportions of a saturated 'monohydric aliphatic alcohol containing irom' 1 to 12 carbon atoms in the presence of an acidesteriilcatlon catalyst, in a solvent selected trom the group consisting of N,N-dimethyliormamide. N,N-dimethylacetamide, N-methyl-2-pyrrolidone, ethylene carbonate, ethylene carbamate. and 'ybutyrolactone.

9. A solution of a resinous composition comprising from 60 to 90 per cent by weight oi'polyacrylonitrile and from 40 to per cent by weight oi an ester-lactone prepared by heating to reacting temperature one molecular proportion oi an equimolar heteropolymer oi maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of ethyl alcohol in the presence of an acid-esteriflcation catalyst, in N,N-di- I methylformamide.

10. A solution of a resinous composition comprising irom 60 to 90 per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight oi an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer oi maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of isopropyl alcohol in the presence of an acld-esterlfication catalyst. in N,N- dimethyliormamide.

11. A solution of a resinous composition comprising from 60 to 90 per cent by weight of polyacrylonitrlle and from 40 to 10 per cent by weight of an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer of maleic anhydride and isopropenyl acetate, with from 2 to 25 molecular proportions of n-amyl alcohol in the presence of an acid-esterification catalyst. in N,N-dimethyli'ormamlde.

12. A solution 01' a resinous composition comprising from 60 to 90 per cent by weight of polyacrylonitrile and from 40 to 10 per cent by weight or an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer oi maleic anhydride and isopropenyl acetate, with from 2 to 25 mo-. lecular proportions of isoamyl alcohol in the presence of an acid-esteriflcation catalyst, in N,N-dimethyltormamide.

18. A resinous composition comprising from 80 to 99 per cent by weight of polyacrylonitrile and from to 10 per cent by weight of an esterlactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer oi maleic anhydride and vinyl acetate, with from 2 to 25 molecular proportions of a' saturated monohydric aliphatic alcohol conv from 1 to 12 carbon atoms in the presence-ot an acid-esteriflcation catalyst.

11. A resinous composition comprising from to per cent by weight 01 polyacryionitrile anqfirom 40 to 10 per cent by weight of an est'e'r -lactone prepared by heating to reacting temperature one molecular proportion of an equimo heteropolymer oi maleic anhydride and viny acetate, with from 2 to 25 molecular proportions 0! ethyl alcohol in the presence of an acidyesterification catalyst.

15. A solution oi a resinous composition comprising from 60 to 90 per cent by weight of polyacrylonitrile and trom 40 to 10 per cent by weight oi an ester-lactone prepared by heating to reacting temperature one molecular proportion of an equimolar heteropolymer oi maleic anhydride and vinyl acetate, with from 2 to 25 molecular proportions of a saturated monohydric aliphatic alcohol containing from 1 to 12 carbon atoms in an acid-esteriflcation catalyst. in N,N-dimethyl- 40 Iorrnamide.

HARRY W. COOVER, J1. JOSEPH B. DICKE'Y.

REFERENCES CITED The following references are 01' record in the ille of this patent:

UNITED STATES PATENTS 

1. A RESINOUS COMPOSITION COMPRISING FROM 60 TO 90 PER CENT BY WEIGHT OF POLYACRYLONITRILE AND FROM 40 TO 10 PER CENT BY WEIGHT OF AN ESTERLACTONE PREPARED BY HEATING TO REACTING TEMPERATURE ONE MOLECULAR PROPORTION OF AN EQUIMOLAR HETEROPOLYMER OF MALEIC ANHYDRIDE AND AN ESTER SELECTED FROM THE GROUP CONSISTING OF VINYL ACETATE AND ISOPROPENYL ACETATE, WITH FROM 2 TO 25 MOLECULAR PROPORTIONS OF A SATURATED MONOHYDRIC ALIPHATIC ALCOHOL CONTAINING FROM 1 TO 12 CARBON ATOMS IN THE PRESENCE OF AN ACID-ESTERIFICATION CATALYST. 